1. Field of the Invention
The present invention relates to a data processing system capable of processing data of different kinds, such as code data representing characters and symbols and image data representing image density.
2. Description of the Prior Art
In the case of processing data of different kinds such as code data representing characters, symbols, etc., and image data representing image density, there may be employed separate transmission channels for transmitting the respective kinds of data for data processing. Such an arrangement is, however, undesirable since there are required plural transmission channels according to the kinds of data, leading to a high cost, particularly in the case of long-distance transmission.
On the other hand, in the case of transmitting data of different kinds through a common transmission channel, it has been necessary to provide the receiving unit with a memory of a large capacity for storing all the transmitted data in said memory and to inspect the stored data for identifying the kind thereof. Such an arrangement is not only costwise undesirable but also is unsuitable for real-time processing since the identification of data content requires time.
In either case, the above-mentioned drawbacks become more serious as the number of kinds of data increases.